"Unlike other “fuels,” energy efficiency does not have a furnace that burns, or even a utility meter and breaker panel box. Energy efficiency is invisible for most people; in fact, it is only present in its absence – like when your utility bills drop. For that reason it has been hard for the average residential real estate agent to effectively communicate energy efficiency benefits to clients. But that’s changing."
http://www.nextstepliving.com/energy-efficiency-and-your-realtor